1. Field
Embodiments of the present invention relate to a battery management system and a method of driving the same.
2. Description of the Related Art
As environmental destruction and resource depletion become more significant, an interest in a system for storing power and efficiently using the stored power has increased.
A power storage system may store generated power of new and renewable energy in a battery or may store power of a commercial system in a battery with relation to the commercial system. The power storage system may supply power stored in the battery to the commercial system or to a load.
A rechargeable secondary battery may be used for the power storage system in order to store power. However, due to limitations on a capacity of the secondary battery, a number of secondary batteries may be coupled in parallel or may be serially coupled to form a battery pack. There exists a variation in capacities of battery cells that form the battery pack due to various causes in manufacturing processes.
Therefore, in the battery pack, a variation is generated in charge and discharge voltages of the battery cells in a charge and discharge cycle. Therefore, in the battery pack, a specific battery cell may be overcharged during charge and a specific battery cell may be over-discharged during discharge. As described above, when a specific battery cell is overcharged or over-discharged in the battery pack, a capacity of the battery pack is reduced, the battery pack is deteriorated, and a lifespan of the battery pack is reduced.
Therefore, a cell balancing operation that keeps uniformity of voltages of the battery cells may be performed. However, the cell balancing operation is performed based on a voltage of a battery cell having a lowest cell voltage so that energy of battery cells having relatively high voltages may be lost.
Hereinafter, a battery management system for reducing (or preventing) energy from being lost by the cell balancing operation is suggested.
The above information disclosed in this Background section is only for enhancement of understanding of the background of embodiments of the present invention and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art.